/*
 * Copyright (c) 2007-2012, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
package com.sun.org.apache.bcel.internal.generic;

/* ====================================================================
 * The Apache Software License, Version 1.1
 *
 * Copyright (c) 2001 The Apache Software Foundation.  All rights
 * reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *
 * 3. The end-user documentation included with the redistribution,
 *    if any, must include the following acknowledgment:
 *       "This product includes software developed by the
 *        Apache Software Foundation (http://www.apache.org/)."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Apache" and "Apache Software Foundation" and
 *    "Apache BCEL" must not be used to endorse or promote products
 *    derived from this software without prior written permission. For
 *    written permission, please contact apache@apache.org.
 *
 * 5. Products derived from this software may not be called "Apache",
 *    "Apache BCEL", nor may "Apache" appear in their name, without
 *    prior written permission of the Apache Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 */

import com.sun.org.apache.bcel.internal.Constants;
import com.sun.org.apache.bcel.internal.classfile.*;
import java.util.ArrayList;

/**
 * Abstract super class for all possible java types, namely basic types
 * such as int, object types like String and array types, e.g. int[]
 *
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 */
public abstract class Type implements java.io.Serializable {
    protected byte type;
    protected String signature; // signature for the type

    /** Predefined constants
     */
    public static final BasicType VOID = new BasicType(Constants.T_VOID);
    public static final BasicType BOOLEAN = new BasicType(Constants.T_BOOLEAN);
    public static final BasicType INT = new BasicType(Constants.T_INT);
    public static final BasicType SHORT = new BasicType(Constants.T_SHORT);
    public static final BasicType BYTE = new BasicType(Constants.T_BYTE);
    public static final BasicType LONG = new BasicType(Constants.T_LONG);
    public static final BasicType DOUBLE = new BasicType(Constants.T_DOUBLE);
    public static final BasicType FLOAT = new BasicType(Constants.T_FLOAT);
    public static final BasicType CHAR = new BasicType(Constants.T_CHAR);
    public static final ObjectType OBJECT = new ObjectType("java.lang.Object");
    public static final ObjectType STRING = new ObjectType("java.lang.String");
    public static final ObjectType STRINGBUFFER = new ObjectType("java.lang.StringBuffer");
    public static final ObjectType THROWABLE = new ObjectType("java.lang.Throwable");
    public static final Type[] NO_ARGS = new Type[0];
    public static final ReferenceType NULL = new ReferenceType() {
    };
    public static final Type UNKNOWN = new Type(Constants.T_UNKNOWN, "<unknown object>") {
    };

    protected Type(byte t, String s) {
        type = t;
        signature = s;
    }

    /**
     * @return signature for given type.
     */
    public String getSignature() {
        return signature;
    }

    /**
     * @return type as defined in Constants
     */
    public byte getType() {
        return type;
    }

    /**
     * @return stack size of this type (2 for long and double, 0 for void, 1 otherwise)
     */
    public int getSize() {
        switch (type) {
            case Constants.T_DOUBLE:
            case Constants.T_LONG:
                return 2;
            case Constants.T_VOID:
                return 0;
            default:
                return 1;
        }
    }

    /**
     * @return Type string, e.g. `int[]'
     */
    public String toString() {
        return ((this.equals(Type.NULL) || (type >= Constants.T_UNKNOWN))) ? signature : Utility.signatureToString(signature, false);
    }

    /**
     * Convert type to Java method signature, e.g. int[] f(java.lang.String x)
     * becomes (Ljava/lang/String;)[I
     *
     * @param return_type what the method returns
     * @param arg_types what are the argument types
     * @return method signature for given type(s).
     */
    public static String getMethodSignature(Type return_type, Type[] arg_types) {
        StringBuffer buf = new StringBuffer("(");
        int length = (arg_types == null) ? 0 : arg_types.length;

        for (int i = 0; i < length; i++)
            buf.append(arg_types[i].getSignature());

        buf.append(')');
        buf.append(return_type.getSignature());

        return buf.toString();
    }

    private static int consumed_chars = 0; // Remember position in string, see getArgumentTypes

    /**
     * Convert signature to a Type object.
     * @param signature signature string such as Ljava/lang/String;
     * @return type object
     */
    public static final Type getType(String signature) throws StringIndexOutOfBoundsException {
        byte type = Utility.typeOfSignature(signature);

        if (type <= Constants.T_VOID) {
            consumed_chars = 1;
            return BasicType.getType(type);
        } else if (type == Constants.T_ARRAY) {
            int dim = 0;
            do { // Count dimensions
                dim++;
            } while (signature.charAt(dim) == '[');

            // Recurse, but just once, if the signature is ok
            Type t = getType(signature.substring(dim));

            consumed_chars += dim; // update counter

            return new ArrayType(t, dim);
        } else { // type == T_REFERENCE
            int index = signature.indexOf(';'); // Look for closing `;'

            if (index < 0)
                throw new ClassFormatException("Invalid signature: " + signature);

            consumed_chars = index + 1; // "Lblabla;" `L' and `;' are removed

            return new ObjectType(signature.substring(1, index).replace('/', '.'));
        }
    }

    /**
     * Convert return value of a method (signature) to a Type object.
     *
     * @param signature signature string such as (Ljava/lang/String;)V
     * @return return type
     */
    public static Type getReturnType(String signature) {
        try {
            // Read return type after `)'
            int index = signature.lastIndexOf(')') + 1;
            return getType(signature.substring(index));
        } catch (StringIndexOutOfBoundsException e) { // Should never occur
            throw new ClassFormatException("Invalid method signature: " + signature);
        }
    }

    /**
     * Convert arguments of a method (signature) to an array of Type objects.
     * @param signature signature string such as (Ljava/lang/String;)V
     * @return array of argument types
     */
    public static Type[] getArgumentTypes(String signature) {
        ArrayList vec = new ArrayList();
        int index;
        Type[] types;

        try { // Read all declarations between for `(' and `)'
            if (signature.charAt(0) != '(')
                throw new ClassFormatException("Invalid method signature: " + signature);

            index = 1; // current string position

            while (signature.charAt(index) != ')') {
                vec.add(getType(signature.substring(index)));
                index += consumed_chars; // update position
            }
        } catch (StringIndexOutOfBoundsException e) { // Should never occur
            throw new ClassFormatException("Invalid method signature: " + signature);
        }

        types = new Type[vec.size()];
        vec.toArray(types);
        return types;
    }

    /** Convert runtime java.lang.Class to BCEL Type object.
     * @param cl Java class
     * @return corresponding Type object
     */
    public static Type getType(java.lang.Class cl) {
        if (cl == null) {
            throw new IllegalArgumentException("Class must not be null");
        }

        /* That's an amzingly easy case, because getName() returns
         * the signature. That's what we would have liked anyway.
         */
        if (cl.isArray()) {
            return getType(cl.getName());
        } else if (cl.isPrimitive()) {
            if (cl == Integer.TYPE) {
                return INT;
            } else if (cl == Void.TYPE) {
                return VOID;
            } else if (cl == Double.TYPE) {
                return DOUBLE;
            } else if (cl == Float.TYPE) {
                return FLOAT;
            } else if (cl == Boolean.TYPE) {
                return BOOLEAN;
            } else if (cl == Byte.TYPE) {
                return BYTE;
            } else if (cl == Short.TYPE) {
                return SHORT;
            } else if (cl == Byte.TYPE) {
                return BYTE;
            } else if (cl == Long.TYPE) {
                return LONG;
            } else if (cl == Character.TYPE) {
                return CHAR;
            } else {
                throw new IllegalStateException("Ooops, what primitive type is " + cl);
            }
        } else { // "Real" class
            return new ObjectType(cl.getName());
        }
    }

    public static String getSignature(java.lang.reflect.Method meth) {
        StringBuffer sb = new StringBuffer("(");
        Class[] params = meth.getParameterTypes(); // avoid clone

        for (int j = 0; j < params.length; j++) {
            sb.append(getType(params[j]).getSignature());
        }

        sb.append(")");
        sb.append(getType(meth.getReturnType()).getSignature());
        return sb.toString();
    }
}
